Polyesters

Fradet, Alain; Tessier, Martine

doi:10.1002/0471220523.ch2

Cited by 24 publications

(29 citation statements)

References 190 publications

(240 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The PHT was obtained in 84% yield with a weight-average molecular weight of 63,000, a T g~1 0 ºC and a T m~1 40 ºC. NMR (CDCl 3 , 300 MHz): δ (ppm) 8 A mixture of cyclic oligomers c(HT) [2][3][4][5] and CL with the selected composition ratio and Sb 2 O 3 (0.5 %-mole), was introduced into a two-necked round-bottom flask equipped with a nitrogen inlet/outlet. The flask was purged with nitrogen to remove all traces of moisture and residual air, and immersed in an oil heating bath.…”

Section: Synthesis Of Cyclic Oligomers C(ht) N By Cyclo-depolymerizatmentioning

confidence: 99%

“…The ring-opening polymerization of the cyclic oligomers c(HT) [2][3][4][5] was carried out at 175 ºC or 200 ºC for 120 min either in the presence of 0.5 %-mole of catalyst (Sb 2 O 3 , DBTO or Sn(Oct) 2 ) or without catalyst. The intrinsic viscosities of the resulting polymers are listed in Table 2 and data available for fraction c(HT) [6][7] [19] were included for comparison.…”

Section: Synthesis Of Pht By Ring-opening Polymerization Of C(ht) Nmentioning

confidence: 99%

“…Aromatic polyesters are typically prepared by step-growth polycondensation in the melt [1,2]. A second option is the ring-opening polymerization (ROP) of cyclic oligoesters under solvent free conditions [3].…”

Section: Introductionmentioning

confidence: 99%

“…In this paper we wish to report again on the preparation of poly(hexamethylene terephthalate-cocaprolactone) copolyesters by ROP, but now using a fraction of cyclic hexamethylene terephthalate oligomers c(HT) [2][3][4][5] enriched in dimmer to pentamer. The aim of the work is to evaluate the influence of the size of the cyclic oligoesters on the ring-opening polymerization reaction and on the structure and properties of the resulting polyesters.…”

Section: Introductionmentioning

confidence: 99%

“…The aim of the work is to evaluate the influence of the size of the cyclic oligoesters on the ring-opening polymerization reaction and on the structure and properties of the resulting polyesters. Firstly the oligomeric c(HT) [2][3][4][5] fraction was prepared by cyclo-depolymerization of PHT and characterized in full detail.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Poly(hexamethylene terephthalate-co-caprolactone) copolymers: Influence of cycle size on ring-opening polymerization

González-Vidal

Ilarduya

Muñoz‐Guerra

2010

European Polymer Journal

View full text Add to dashboard Cite

Poly(hexamethylene terephthalate) was cyclo-depolymerized in solution by heating to yield a fraction of cyclic oligomers of hexamethylene terephthalate (c(HT) 2-5 ) with a content around to 95% in dimer to pentamer. Ring-opening polymerization in the melt of c(HT) 2-5 , either neat or in mixtures with ε-caprolactone (CL) covering a range of HT/CL ratios from 9/1 to 1/9 was carried out to produce polyesters with molecular weights above 30,000 in high yields. The copolyesters had a comonomer composition according to the feed and the microstructure evolved from random to blocky as the content in CL increases. The thermal and mechanical properties of the copolyesters were evaluated for a variety of compositions. Results obtained in this work were compared to those previously obtained by us in the ring-opening copolymerization of CL with a cyclic oligomeric fraction enriched in hexamer and heptamer (c(HT) 6-7 ). Although the polyesters resulting from the use of these two fractions were similar, significant differences were found in polymerization rate evidencing a lower reactivity of c(HT) n with decreasing values of n.

show abstract